Mansion for Rent for a wedding

Does anyone out there have any ideas as to where you can rent a mansion in the Vancouver and outlying areas for a couple of days to do a wedding and not be bound to any catering etc. I have no idea why it's so hard to book a big fancy house that would sleep 30 but they seem to all say, no parties or weddings. A wedding would be less of a threat of damage than simply having 30 people over a random party that is meant to just party. Willing to pay a huge deposit even...harder than i thought this idea would be. Thank you all.